Fix implicit nullable parameters deprecation for PHP 8.4 (#1)

* Fix Implicitly marking parameter $maxItems as nullable is deprecated [0203813]

* Change maxItems parameter to nullable integer [542215a]

* Fix implicit nullable parameters deprecation in unit tests [43614f1]

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Co-authored-by: Daniel Rudolf <[email protected]>

SequentialArray + ArrayHasItemWith: Update README.md to explain Itera…

…tor handling

Enable Psalm static code analysis for PHPUnit tests

Composer: Update branch alias 'dev-master' == 'v1.1.x'

Unify phplucidframe/console-table line endings